1. Field of the Invention
The present invention relates to a retractable blade utility knife, and more particularly to a retractable blade utility knife that allows for the storage of spare blades within the knife handle and that allows for the replacement of knife blades without disassembly of the knife handle. Furthermore, the present invention relates to a utility knife that includes an ergonomically shaped handle or body, a cutting blade movable in the body to extend a cutting portion of the blade outwardly of the body at one end of the knife body, externally accessible means for moving the cutting blade between the extended cutting position and a retracted position of withdrawal into the handle, the same externally accessible means for moving the cutting blade also allowing for movement of the cutting blade to a position wherein the blade can be replaced with a spare blade, and provision for storage of several spare blades within the knife handle.
2. Related Art
The field of utility knives includes many examples of previous attempts to provide a utility knife that satisfies one or more of the many concerns for such knives. Related knives include knives that have handles providing a forward longitudinal cavity in which a blade carrier member is slidably received, and a rear cavity in which a number of spare blades are received. In existing knives, the blade carrier member carries a double-ended cutting blade, and is movable longitudinally of the forward cavity between a retracted safety position with the blade entirely within the handle, and an extended cutting position in which a triangular end part of the blade extends forwardly out of the handle. The handle is vertically split and includes two portions which are almost mirror images of one another. A screw secures the handle portions together and allows their separation with the use of a screwdriver for substituting one of the spare blades for a used cutting blade.
Existing utility knives also include knives in which blades may be changed without disassembly of the handles by forward extension therefrom of a forward part of a channel-like blade carrier member. Existing knives also include knives in which the handle halves are connected by a pivot positioned intermediate along the length of the handle, and are movable about the pivot between open and closed positions. In such knives, a blade carrier is mounted between the handle halves and the blade carrier is adapted for reciprocal movement toward and away from the blade receiving opening.
A typical shortcoming of existing retractable blade utility knives is the lack of a knife that includes both a means for replacing used blades with new blades without disassembly of the handles, and providing a means for storage of spare blades within the knife handles.
Another shortcoming of existing retractable blade utility knives is the lack of a knife that includes means for actuating the knife blade carrier to a position for loading of a new knife blade and then, in one continuous motion, actuating the knife blade carrier to a position wherein the knife blade is extended from the knife handle for use, all without requiring any disassembly of the knife.